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You have files VendingMachine.java, Cola.java, and a driver class named Driver.java. Fill in the correct visibility modifiers so that the comments in the class Cola and Driver’s main method are upheld. public class VendingMachine {   1 void pay() { /*compiles*/ }   2 void shake() { /*compiles*/ }   3 void choose() { /*compiles*/ } } —– in a separate file in a different package/directory —– public class Cola extends VendingMachine {   public void cocaCola() { pay(); // doesn’t compile choose(); // compiles }} —– in a separate file in a different package/directory —– public class Driver { public static void main(String[] args) {        Cola c = new Cola();         c.pay();   // doesn’t compile        c.shake(); // compiles c.choose(); // doesn’t compile }}   1   : [1]  2   : [2]  3   : [3]

Assume class Child inherits from class Parent. We can instantiate an abstract Child class as long as a concrete Parent class exists by writing the following statement: Child c = new Child();

Analyze the following code and indicate, for each line, whether autoboxing, unboxing, or neither occurs when the assignment operator is evaluated: boolean a = new Boolean(true); // 1 occurs Boolean b = a; // 2 occurs   1   : [1]   2   : [2]

Analyze the following code and indicate, for each line, whether autoboxing, unboxing, or neither occurs when the assignment operator is evaluated: Character c = ‘b’; //  1   occurschar a = c; //  2   occurs   1   : [1]   2   : [2]

Given the following class hierarchy, identify whether the method drive is overloaded, overridden, or neither by the subclass:  public class Car {   public void drive(int miles) { /* implemented */ } } public class Ford extends Car {   public void drive(int miles, String name) { /* implemented */ } }

Analyze the following code and indicate, for each line, whether autoboxing, unboxing, or neither occurs when the assignment operator is evaluated: Character c = ‘b’; //  1   occurschar a = c; //  2   occurs   1   : [1]   2   : [2]

Given the following class hierarchy, identify whether the method drive is overloaded, overridden, or neither by the subclass:  public class Car {   public void drive(int miles) { /* implemented */ } } public class Ford extends Car {   public void drive(int miles, String name) { /* implemented */ } }

                . ‘  .           ‘ .( ‘.) ‘     _   (‘-.)’ (`’.) ‘     | (- -(. ‘) WRAPPER (-) ‘  .–`+’-. .  (‘ CLASSES ‘) .  |`—-‘|   (‘ .) – (‘. )  | /..\ |    . (‘ `.  )   |\./\.\|      ` .  `   |./G \/|  |.\ T/.|  `-._/.-‘

Complete the Javadoc comments for the following method:    1     Computes the number of hours practiced on an instrument   based on the pages of sheet music.     2   sheetMusic The number of pages of music     3   Method returns how long instrument has been played */ public String practice( int sheetMusic ) {     return String.format(“Practiced %s for %.2f hours”, this.instrument, sheetMusic * 0.15); }    1  : [1]   2  : [2]   3  : [3]

Complete the Javadoc comments for the following method:    1     Computes the number of hours practiced on an instrument   based on the pages of sheet music.     2   sheetMusic The number of pages of music     3   Method returns how long instrument has been played */ public String practice( int sheetMusic ) {     return String.format(“Practiced %s for %.2f hours”, this.instrument, sheetMusic * 0.15); }    1  : [1]   2  : [2]   3  : [3]